Economics Lectures - [1 - 2 - 3 - 4 - 5 - 6 - 7 - 8 - 9 - 10 - 11 - 12 - 13 - 14]
This lecture is the final review for this course, in preparation for the final exam. A student who took this class in 2007 sent me the following feedback from college:
“ | My microeconomics class has been almost all review for me, because of the similar class I took from Mr. Andy Schlafly .... Although other students who attended public schools may have taken 'economics' before, they have struggled with microeconomics this semester, because their high school classes completely ignored the free-market and Austrian economics[1] which are taught [in college]. | ” |
Let's begin this lecture by summarizing the percentages the CLEP exam devoted to particular topics. This will help organize the material we have covered in this course. Our online final exam next week will use a similar distribution in topics as the CLEP exam, but without over-emphasizing government policy.
Here is a list of the topics on the CLEP exam, along with how many questions are asked about each topic (as a percentage of the overall exam), plus tips about each concept:
cost measures (e.g., ATC, AFC, AVC) | 10% | FC is total cost when output is zero; convert to average costs by dividing by output. Remember that ATC=AFC+AVC, and know when a firm should shut down. |
Government policy | 10% | price ceilings cause shortages and taxes cause social (deadweight) loss; but beware of CLEP questions designed to make government regulation appear beneficial, as in reducing pollution |
Inputs to a Firm (espec. labor) | 10% | key here is applying logic and other concepts to reason back from product demand to a firm's need for labor (workers); know effects of minimum wage laws; might also be asked about capital |
Perfect Competition | 6% | costs and profits and price are lowest for this type of market. P=MC=ATC and "economic profits" are squeezed to zero. If price falls, shut down in short run when P<AVC; shut down in long run when P<ATC. |
Monopolistic Competition | 6% | can set its price above MC, but the low barrier to entry allows competitive forces that prevent long run profits and require P=ATC |
Production Possibilities | 6% | trade-off among goods made by a nation; to reach points beyond the "frontier" (curve), it requires a technological advance or other big change |
Price Elasticity | 5% | measures how demand responds to price changes; "elastic" means big change in demand for a small change in price of good |
Monopoly | 4% | the firm sets its price above marginal cost, but not higher than where MR=MC; economic profits are greater than zero; economic rent exists. P>MC. P>ATC. |
Demand Curve | 4% | what the public will pay; all firms in all kinds of markets are restrained by the Law of Demand |
MR | 4% | marginal revenue is the increase in total revenue due to selling one more unit; profit maximized where MR=MC |
MC | 4% | marginal cost, which equals price in perfect competition. For a monopoly P>MC but equals MR=MC |
Public Goods | 3% | know the difference between these and private goods: public goods cannot exclude people from using the good without paying for it. |
Returns to Scale | 2% | think of Wal-Mart for increasing returns to scale; think of a kitchen for decreasing returns to scale ("too many cooks spoil the broth") |
Consumer Surplus | 2% | what someone was willing to pay above what the good actually cost |
Comparative Advantage | 2% | nation with lower production costs should do what it does best |
Oligopoly | 2% | only a few firms, like two gas stations at an intersection far away from any others; usually one Nash Equilibrium-type exam question |
Imperfect Competition | 2% | P>MC for this market, which is "allocatively inefficient" (is not efficient in the allocation of resources); it takes perfect competition to drive P down to MC |
Utility | 2% | overall satisfaction; recall our problem about hiking and reading. Marginal utility is your next bit of utility. Indifference curve shows trade-off in utility. |
Cross-Price Elasticity | 2% | Comparing change in demand for one good due to change in price for a different good |
Opportunity Cost | 2% | keep in mind that "economic costs" include opportunity costs in addition to actual out-of-pocket (accounting) costs |
Substitutes | 2% | think Coke versus Pepsi |
Complements | 2% | think ketchup with French fries |
Long Run v. Short Run | 2% | in the long run all costs are variable and can be minimized; short and long run mentioned in 20% of questions, to distinguish between quick changes and permanent ones |
Externalities | 2% | two types: positive (music in an open-air park) and negative (pollution) |
Inferior v. Normal Goods | 1% | when income goes up, demand for an inferior good or service goes down (e.g., demand for bankruptcy services) |
substitution and income effects | 1% | increase in price means less demand because public uses substitutes (substitution effect of price increase) and becomes poorer (income effect of price increase) |
Cartel | 1% | an oligopoly that illegally agrees to fix (set) prices, as OPEC does |
Price discrimination | 1% | charging different prices for the exact same good; only possible if the market allows the firm to set its own price |
Some important topics are missing from the CLEP exam, such as the invisible hand, free market, charity, transaction costs, the time value of money, interest rates, the Coase theorem and Gresham's Law. The reason is exam bias. For example, once a student realizes how inefficient transaction costs are, he or she will probably not like government regulations much! Instead of these concepts, the CLEP exam adds lots of questions about government regulation to try to make regulation look good. But other than bias in the selection of question, bias is rare in answers to economics questions. Pick the answer that you think is correct, without worrying about bias.
As always, be sure you fully understand the question before you answer it, and use common sense and logic. In fact, many economics questions can be answered correctly with patience and basic reasoning skills.
Let's put our knowledge from this course to good use in studying for our final exam, and preparing for the CLEP exam. We maximize our utility by scoring as high as possible on these exams. To do so, we need to maximize our marginal utility in allocating our time towards the exam topics listed above. If we spend all our studying time on "price discrimination," which is only 1% of the exam, then we are not maximizing our marginal utility and will not reach our full potential.
This is similar to our homework problem earlier in the course about maximizing our marginal utility with respect to hiking and reading. This time, however, the decision each student must make is which topic to focus on first in the above list, and how much time to spend on it before moving on to another topic in the list. The answer may be different for each student.
This same challenge in optimizing strategy could be expressed as a problem of "allocative efficency": allocating resources (time and information) in the most efficient way. Just as efficiency is essential to successful businesses, efficiency is also important to becoming a successful student. Spending your time efficiently in preparing for the final exam, and preparing for the CLEP, is crucial to your ability to do well on them. Look at the above list of topics and how often they appear, and ask yourself: where should you focus first in order to pick up the most points in the shortest amount of time?
Should you simply start reviewing at the top of the list and work your way down to the bottom? That strategy has the advantage of focusing on the most important topics first. If you run out of time in reviewing, then you will miss only the less important topics. But you might improve further on that strategy by moving more quickly through topics that you already understand well. Alternative, there may be topics that you find too difficult to understand, and you might give up some points there in order to focus better on topics where you can pick up more points.
For the rest of this class this lecture will focus on topics which might provide the greatest marginal increase in your exam scores. This takes into consideration the topics we have already reviewed (you have the materials for those), and avoids duplication of that review. You may, however, decide for yourself that you can benefit most from reviewing those prior topics.
Your instructor emphasizes studying strategy for a reason. The biggest reason why some students do not succeed is a lack of effort. But the second biggest reason is poor studying and test-taking strategies, like a football team that runs ill-advised plays. Education, like business and perhaps even life itself, rewards good strategies and punishes misguided ones.
For many students, the most additional points can be obtained by reviewing the "Inputs to a Firm" category. It will be on 10% of the questions on the final exam and the CLEP exam. That's a significant chunk of these exams. Without review, these questions look hard and are easy to miss. But with some extra preparation, you should be able to answer nearly all of them correctly. In maximizing your score and making the best use of your time, this category may result in the biggest increase in correct answers with the least amount of effort. That's what maximizing marginal utility is all about.
Accordingly, in economic terms, the greatest marginal utility from studying for the exam is probably obtaining by focusing on this topic first. We've already covered the other two topics comprising 10% apiece of the exam (cost measures and government regulation), so there may not be many more points to pick up there. Realize that you will probably get some exam questions right without additional studying, and other questions you may get wrong no matter how much you study. But in this category of "inputs to a firm," you can pick up some points that you would otherwise miss. Let's review it now.
Questions about inputs to a firm focus on what a firm will do with its inputs (typically labor, but sometimes capital) in order to maximize its profits. The questions usually concern the following:
Review the above list now. How many of the above 8 topics do you know well enough to answer a question about them correctly? Let's briefly review each of these concepts so you can maximize your score on this big part of the exam.
1. "the impact of an improvement in technology on the production by a firm"
2. "adjusting inputs to minimize the overall cost at a constant level of output"
3. "the effect of the minimum wage on the competition for labor"
4. "comparing the cost of an input (usually labor) relative to the additional revenue that results"
5. "why a firm's "demand for labor" is called a "derived demand"
6. "what causes an increase in demand for labor"
7. "the relation between hiring additional workers and the marginal cost"
8. "calculating overall costs (total cost and average variable cost) based on wages"
Master the above eight issues, and you'll convert 10% of the exam from wrong answers to correct ones. That could enable you to earn college credit.
You instructor wonders what topic will maximize our marginal utility next. About 20% of the exam is devoted to questions about different types of markets, ranging from the most advantageous for the public (perfect competition) to the least advantageous for the public (monopoly). That's a large chunk of questions, and with some extra review here students can convert potentially wrong answers into correct ones.
The key to answering these questions correctly is to realize that the more competition there is, the lower the price of the goods and services and the lower the profits for the firms. Some of these questions are special cases and should simply be memorized: a cartel is an oligopoly that illegally agrees to fix (set) its prices, and an oligopoly is an industry where just a few firms dominate the market. When given a grid about where an oligopoly ends up selling its goods (its Nash Equilibrium), the answer is always symmetric (all firms sell at the same price) and usually not the highest price that a monopoly could sell at.
The monopoly questions look harder than they really are. The monopolist sets his price higher than marginal cost, which would be the optimal price from the standpoint of the public (or government). Instead, the monopolist price sets his price where marginal revenue equals marginal cost (MR=MC). If shown a graph, you may have to find the quantity where MR=MC, and then find the corresponding price on the demand curve. Notice that a monopolist has no supply curve, because a supply curve represents many firms in an industry and a monopolist is the only firm in the industry.
There can be general questions about these markets. A perfectly competitive market uses resources in a perfectly efficient way. At the other end of the spectrum, a monopoly uses resources the least efficiently of all. Its high pricing causes a huge social loss ("deadweight loss") by eliminating consumer surplus. The monopoly reduces output in order to cause a scarcity that increases the price to an artificially high level. This is bad for everyone, except the owner of the monopoly, who enriches himself. This is how Bill Gates became the wealthiest person in the world.
Here is a puzzle to leave you with. What is the impact on quantity of a price ceiling in a competitive industry compared to a price ceiling in a monopoly? In which one (competitive v. monopoly) might a clever price ceiling actually increase quantity? Think about it, and learn to ask yourself questions like this in order to master economics. The answer is in this footnote.[2]
Be sure to spend time on the review sections in the prior lectures for more information about this and other topics on the exams.
A public good is a good which is nonexcludable and nondepletable. The first condition means that it is impossible to exclude consumers from partaking in the good, and the second condition means that one consumer's consumption of the good does not prevent others from consuming it.
Explained another way, a public good is available to all such that consumption by one person does not reduce its availability to others. An example of a public good is national defense, as it protects everyone and its benefits to one person do not diminish its benefits to others.
Other examples of public goods are law enforcement (protection by the police), public fireworks, clear air, street lights, radio and television transmissions, lighthouses, and some inventions. Some of these examples, such as lighthouses, are contested as to whether they must be a public good, as it is possible to charge ships port fees to pay for them. Also, while radio and television transmissions are available to all to receive them, it does cost money to buy radios and television sets, so these are not truly public goods either.
Liberals like to emphasize the concept of public goods on exams in order to support the argument for more government. Under this view public goods represent market failure and the need for government services supported by taxes.
Good test-taking techniques are particularly important to doing well on an economics exam. Simple questions are often intentionally disguised as something more complicated. It is easy to become confused and misguided in analyzing economic issues. 99% of the public would say that we would be better off if Congress put a price ceiling or cap on gasoline at $1 a gallon. It takes a bit more thought to realize that massive shortages would result, and we would all have to waste hours each week waiting in line for gasoline. Some who really need gas in hurry, such as people trying to take someone to a hospital, may not be able to obtain gas in time.
The ability to eliminate wrong answers can help. Let’s try the elimination technique on these questions:
Question: Consider the poverty-level of income for a family of four in America. Which of the following can be said about how the government defines this specific income level?
Virtually none of you would know the answer to this question at first glance. This question is not really appropriate for a "micro"-economics exam ("micro"-economics concerns individual buying and selling decisions), but CLEP asks it anyway. Questions about poverty, gaps between the rich and poor, and government programs are always favorites among liberal educators. You will see many more questions about these issues than about the invisible hand or the creation of wealth.
So what do we do when faced with this question? Simply give up? Move to the next question and hope it is easier? Blindly guess at an answer? None of the above.
We can narrow the choices, and thereby reduce our risk of error, by eliminating wrong answers. Basic economic principles (or common sense) serve as our guide.
Let’s start with choice (C). Think about it: is half of our nation living in poverty? What would that mean for elections? Who would pay to run government? If we called half of us "poor", then what word would be use for the really poor? Choice (C) can't be true. Using common sense, we can eliminate this answer.
Let’s turn to choice (E). Why wouldn’t it be adjusted? Poverty must be relative to the cost of living. If the cost of living doubled, then the numbers in poverty would increase greatly. But failure to adjust for the cost of living would miss that effect. Again, common sense leads us to eliminate this answer.
Next we can turn to choice (A). That doesn't work either, because everyone who pays into Social Security has a right to receive benefits when they grow old, regardless of whether they are rich or poor. “Social security” is not “security only if you’re poor.” We can eliminate this choice.
We’re left with only two possibilities: (B) and (D). Realize that has increased our odds of choosing the right answer to 50% now. If you took the CLEP and at least narrowed every difficult question down to two choices, then you would likely pass the test. How do we next make our best choice among these final two options?
Option (D) seems to have the right amount of detail, and fits the question well grammatically. In contrast, Option (B) does not fit the question as well or make as much sense (definition of what the poverty level is should not change based on distributing some benefits). Even if you had no idea between (B) and (D), (D) is a better fit. It’s our best guess. (D), indeed, is correct.
It helps to choose an answer that gives the most meaning to the purpose of the question. The purpose of this question is to ask about how poverty-level income is calculated. Answer (D) most directly furthers that goal. It makes for a good guess if you did not otherwise know. You won’t always be able to guess the right answers, but by increasing your chances you can significantly increase your overall score.
Let’s try one more CLEP-inspired question, this time relating to labor:
Question: Assume a perfectly competitive market for both inputs and output. If capital is fixed and the price for the output increases, then a firm in the short run will increase its production by which of the following ways:
This type of question benefits from being reread. “Capital is fixed,” according to the question. So capital cannot be increased. Answers (A) and (C) can be eliminated that easily. Many students sometimes miss the obvious on economics exams. They fail to read and understand the question.
Only labor can be increased, which is possible under answers (B), (D) and (E). We've improved our odds of success to a 33% chance. Those are good odds on a difficult question like this. But we can improve our chances even more.
(B) and (D) look similar so let’s turn to (E) first. The “marginal product of labor” is the additional units (“product”) produced due to an additional unit of labor. Remember “MP”? The term does not include “revenue” or “price”, so it only gives you the quantity. We need to multiply that quantity by product price to obtain revenue, what the firm owner cares the most about. Choice (E) makes no sense by dividing terms that should be multiplied together. We can eliminate it.
Back to (B) and (D). The only difference between the two is the term “value of” in (B). Think about what “marginal product” is. It is a quantity, not a dollar amount. Yet we are comparing it to “wage rate,” which would be in dollars. We need to insert “value of” to convert a quantity into equivalent dollars. (B) is must be the correct choice because it compares dollars to dollars, while choice (D) does not.
The key to good test-taking, particularly on economics exams, is to make sure you fully understand each question before trying to answer it.
There are only two or three questions (out of nearly 100) on the CLEP exam that have biased answers. They concern regulation and efficiency. You can expect to see one or two CLEP questions where the correct answer is to support government regulation against pollution. The best way to think about pollution is in terms of its "negative externality," but the CLEP exam writers cast the issue in terms of an efficient use of resources. Under this view, pollution is inefficient because it results in inefficient harm to the environment. Laws against pollution supposedly increase efficiency by preventing harm to the "resource" of the environment. These regulations that prohibit pollution cause less output but supposedly ensure a more efficient use of environmental resources.
While most of us support a cleaner environment, efficiency is usually associated with greater output, not less output. Government regulations almost never improve efficiency; the free market does that best without government interference. That said, you can pick up one or two easy points on the CLEP exam by assuming that environmental regulation increases efficiency by protecting the "resource" of the environment for its better uses.
When companies are allowed to pollute without paying for it, their marginal cost (MC) is artificially lower than it should be. These companies are avoiding the cost of their own pollution. A lower MC means they will produce more goods than if their MC were higher. The term “marginal social cost” is used by economists to represent the true cost of their activities, including the cost of their pollution. Because companies produce more than they would if they had to pay for the cost of their pollution, some consider this to be inefficient. On the CLEP exam, it takes regulation to make it efficient by preventing the companies from putting out the pollution.
You might wonder what a conservative, free market approach to reducing negative externalities (like pollution) would be. One approach would be to require full disclosure to the public by companies of their negative externalities, so that the public could stop buying the companies' products if the public were concerned about the negative externalities. This would enable the free market to solve this problem in an efficient way.
Outside the topic of government regulation on the CLEP exam, there are no biased answers. Do not choose one answer instead of another for reasons of bias except in one or two rare cases.
In areas unrelated to pollution, government establishes price floors, supports and ceilings. Do we all recall the differences? Price “ceilings” (or controls) are the easiest: the government says that the good cannot be sold for a higher price. Just as you cannot reach above your ceiling, the price is prohibited from rising above the ceiling that the government sets for it. It would be requiring gas to be sold for no more than $1.50, for example. The quantity supplied will decrease (move down the supply curve), while the quantity demanded will increase (move up the demand curve). Shortages result from price ceilings.
What is a price floor? Just the opposite of a ceiling. We cannot reach below the floor, and a price floor prevents the price from falling below a certain level. It would be a government law that prohibited milk from selling for less than $2 a gallon, for example. It would be intended to help the suppliers, such as dairy farmers. What happens when government imposes a price floor? There is a surplus of the good, as supply exceeds demand.
Now, how about a price support? That occurs when the government buys large quantities of good, such food, at prices higher than the competitive equilibrium. The government does this to “support” a higher price, instead of passing a law to require a higher price. A price support is designed to help the firms producing the goods, such as farmers. The rationale is that farmers are politically important and that pure competition is too brutal on their business and their lives, and also that foreign countries engage in the same practices. The effect of a “price support” is similar to a price floor: it creates a surplus of the good when the support is above the equilibrium price
When government regulates labor, the analysis is similar to its regulation of price. A “price floor” is created by the minimum wage: the buyer (an employer) must pay at least a certain amount for a service (labor). The minimum wage creates an oversupply of the service: too many workers. Not all of them will be able to obtain jobs at a wage higher than equilibrium. Unemployment results from a minimum wage that is higher than the equilibrium wage.
You have all learned a great deal of material in this course, information that will help you the rest of your lives. The insights and powerful concepts covered by this course can yield greater and greater benefits the more you think about them. Every week I see still something new and helpful in concepts taught in this course. Many students say that this is the best course they took from me, among other helpful courses. Use this course for your benefit.
If there is one unifying theme to this course, then I suggest it is summarized in Jesus's Parable of the Talents. Be productive, and God can multiply the benefits of your work. If you reach out, if you do more, if you make good use of your time, if you maximize your efficiency, if you consider the opportunity costs, and if you increase your output, then you give God more to work with. But if you bury your talents in the ground or if you are like the tree that does not bear fruit, then you give God less for His purpose.
Carpe diem. And be the good that drives out the bad as we discussed in connection with Gresham's Law.
Read this lecture and study for the final exam, which will be the first week in June. It will be 30 multiple-choice questions, similar in format to the quizzes.
Categories: [Economics lectures]